Reactions of Alkali Metals with Water

The video demonstrates the reactions of various metals with water, starting with lithium and sodium, which produce hydrogen gas. Potassium reacts rapidly, igniting the hydrogen gas. Calcium also reacts, and a dye indicates the formation of a base. Observations are encouraged.

What gas is produced when lithium and sodium react with water?

• Nitrogen

• Oxygen

• Hydrogen

• Carbon Dioxide

What happens when potassium reacts with water?

• It does not react

• It forms a solid precipitate

• It dissolves slowly

• It reacts vigorously and ignites

Why does the hydrogen gas ignite during the potassium reaction?

• Due to the presence of a catalyst

• Because potassium is a non-metal

• Because of the high energy produced

• Due to the presence of oxygen

What is the purpose of the dye added to the water?

• To indicate the presence of a base

• To neutralize the reaction

• To change the color of the water

• To react with calcium

What observation is made about sodium during the calcium reaction?

• It evaporates

• It changes color

• It skids on the water surface

• It sinks to the bottom